RFR 8206423: Use ConcurrentHashTable for ResolvedMethodTable

[David Holmes]

Hi Patricio,

On 18/08/2018 4:42 AM, Patricio Chilano wrote:
> Hi Gerard,
> 
> Thanks for the review! Here is the new webrev with the suggested changes:
> 
> Webrev URL: 
> http://cr.openjdk.java.net/~coleenp/8206423.02/webrev/index.html

This seems fine to me. One minor nit - this comment:

  159 // This is done late during GC.
  160 void ResolvedMethodTable::unlink() {

is no longer accurate in resolvedMethodTable.cpp

Thanks,
David

> Thanks,
> Patricio
> 
> On 8/17/18 12:40 PM, Gerard Ziemski wrote:
>> hi Patricio,
>>
>> Looks good. The only feedback I have is that, I’d prefer to see the 
>> names in src/hotspot/share/runtime/serviceThread.cpp use similar 
>> naming convention, so maybe something like:
>>
>>       bool string_table_work = false;
>>       bool symbol_table_work = false;
>>       bool resolved_method_table_work = false;
>> ...
>>                 !(string_table_work = StringTable::has_work()) &&
>>                 !(symbol_table_work = SymbolTable::has_work()) &&
>>                 !(resolved_method_table_work = 
>> ResolvedMethodTable::has_work())) {
>>
>>
>> cheers
>>
>>
>>> On Aug 17, 2018, at 11:08 AM, Patricio 
>>> Chilano<patricio.chilano.mateo at oracle.com>  wrote:
>>>
>>> Hi all,
>>> Could you review this fix that moves the cleanup up of dead entries 
>>> in the resolved method table from the VMThread to the ServiceThread.
>>> The goal was to remove the need to clean up dead entries in the 
>>> resolved method table during safepoints, thus reducing pause times. 
>>> That task was moved to the ServiceThread, which will be notified by 
>>> the VMThread when detecting the need to cleanup after class 
>>> unloading. Benchmarks where run(javac, sanity, SPECjbb) showing 
>>> non-significant results.
>>> The fix was tested with Mach5 on tiers 1, 2, 3 on all platforms. 
>>> (Note: test/hotspot/jtreg/runtime/MemberName/MemberNameLeak.java 
>>> already exists and tests the creation and deletion of entries in the 
>>> resolved method table).
>>> Bug URL:https://bugs.openjdk.java.net/browse/JDK-8206423
>>> Webrev 
>>> URL:http://cr.openjdk.java.net/~coleenp/8206423.01/webrev/index.html  
>>> <http://cr.openjdk.java.net/%7Ecoleenp/8206470.01/webrev/index.html>
>>> Thanks,
>>> Patricio
>>>
>>>
>